Internal tissue retractor

ABSTRACT

A positionable internal retraction device is provided comprising a malleable ring member and a web-like structure. The retraction device operates to temporarily reposition tissues and organs from an operative site to provide a clear access and visual path for the surgeon. The ring member may be elongated, twisted, folded, bent or deformed to provide an appropriate insertion profile and subsequent functional shape. The retraction device may be shaped for both open and minimally invasive surgeries. The retraction device is atraumatic and may be used for retraction of delicate tissues and organs. The ring member may have different bending biases. The web-like structure may be constructed of any elastic material that can stretch and recover from the shaping and reshaping of the ring member. In another aspect of the invention, the ring member further comprises an internal lumen defining a wall, which may be of any geometric shape providing a desired bending bias. The ring member may further include a reinforcement member placed within the lumen and made of a “shape memory” material that allows the reinforcement member to return to its desired shape or condition after being bent. The reinforcement member may be placed in some sections of the ring member to keep these sections substantially straight. Each of the ring member, the reinforcement member and the internal wall may have a cross-section or profile of any geometric shape to provide a desired bending bias in a preferred plane. In yet another aspect of the invention, the ring member further comprises a second lumen and a second reinforcement member placed within the second lumen to provide a desired bending bias.

This is a non-provisional application claiming the priority ofprovisional application Ser. No. 60/442,390, filed on Jan. 24, 2003,entitled “Internal Tissue Retractor,” which is fully incorporated hereinby reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to surgical retractors and, inparticular, to a retractor for retracting tissues and organs tofacilitate access and viewing during a surgical procedure.

2. Discussion of the Prior Art

Surgical procedures often require temporary retraction of surroundingtissues and organs from the immediate surgical site to provide an accessand viewing path for the surgeon. In the prior art, clamps, towels andother makeshift methods have been used to separate and hold structuresin a preferred position away from the point of surgery. Retractors havebeen developed to push and hold tissues and organs away from thesurgical site. These devices typically include paddles and/orcollapsible fingers that expand after the retractors have been insertedinto the body. The retractors may include expandable frames forsupporting expandable sheaths or covers. While some of these deviceshave been successfully used for smaller tissues and organs, the currentretractors have had difficulty in clearing the surgical field of largerand more slippery tissues and organs. In particular, the shape, size andfragility of the tissues and organs may present problems during surgery.For example, large, soft organs such as the intestines and/or stomachare often more difficult to retract and hold in place than from harder,less slippery tissues such as the muscles.

Another drawback of the current retraction devices is they typicallyneed to be attached to an external device to provide support and/ormanipulation. These devices often need to be over-tightened orcompressed to maintain a proper grip and position on the tissues andorgans, which may cause damage to delicate tissues and organs. Moreover,a large surgical incision must be made to accommodate all the componentsof the retraction device. As a result, the surgical site may becomecluttered and encumbered by the many additional components of theretraction device. Therefore, there is a need in the art for aretraction device that can be flexibly utilized to clear a surgical siteof tissues and organs having different shapes, sizes and fragility. Theretraction device should be atraumatic and be able to twist, fold orbend to facilitate insertion and removal.

SUMMARY OF THE INVENTION

The present invention is directed to a positionable internal retractiondevice providing an operable area while holding adjacent structures in adesired position. The retraction device comprises a malleable ringmember that supports a web-like structure. The ring member may beelongated, twisted, folded, bent or deformed to provide an appropriateinsertion profile and subsequent functional shape. The retraction devicemay be shaped for both open and minimally invasive surgeries. Theretraction device is atraumatic and may be used for retraction ofdelicate tissues and organs. The ring member may have differentcross-sectional construction providing different bending biases. Thering member may include a lumen sized and configured to receive areinforcement member providing a desired bending bias in a preferredplane. The reinforcement member may comprise a “shape memory” materialthat enables the reinforcement member to return to its desired shape orcondition after being bent.

The web-like structure is constructed of an elastic material such as abias-woven or knitted fabric that can stretch and recover from theshaping and reshaping of the ring member. The web-like structureoperates to retain the body tissues and organs of different shapes andsizes. More particularly, the web-like structure is able to retain bothhard and soft body tissues and organs during surgery. It is preferablethat the web-like structure is a transparent membrane.

In another aspect of the invention, the ring member further comprises aninternal lumen defining a wall, which may be of any geometric shapeproviding a desired bending bias. The ring member may further comprise areinforcement member placed within the lumen to provide additionalbending bias. The reinforcement member may be formed of a plasticcomponent, a metallic component or any combination thereof. The metalliccomponent includes at least one of aluminum, titanium, stainless steeland Nitenol. In the above aspect of the invention, the reinforcementmember may be placed in some sections of the ring member to keep thesesections substantially straight. It is appreciated that each of the ringmember, the reinforcement member and the internal wall may have across-section or profile of any geometric shape to provide a desiredbending bias in a preferred plane. In yet another aspect of theinvention, the ring member further comprises a second lumen and a secondreinforcement member placed within the second lumen to provide a desiredbending bias.

DESCRIPTION OF THE DRAWINGS

FIGS. 1(a) and 1(b) illustrate the arterial and venous systems,respectively, of a human being;

FIG. 2 illustrates an abdominal region of a human being that may have tobe retracted during a surgical procedure;

FIG. 3 illustrates a retraction device of the present inventionpositioned to relocate a portion of the intestines;

FIG. 4 illustrates a ring member of a retraction device of the presentinvention formed in a first condition;

FIG. 5 illustrates a ring member of a retraction device of the presentinvention formed in a second condition.

FIG. 6 illustrates a perspective view of a ring member of a retractiondevice of the present invention formed in accordance with anotherembodiment of the invention;

FIG. 7 illustrates a perspective view of a ring member of a retractiondevice having a web structure formed on a back side of the ring member;

FIG. 8 illustrates a perspective view of a ring member of a retractiondevice having a web structure formed on a front side of the ring member;

FIGS. 9-11 illustrate the steps of inserting a retraction device of thepresent invention into an abdominal region of a human body;

FIG. 12 illustrates a retraction device of the present invention havinga knitted web member as it is being held prior to insertion into asurgical incision of a body;

FIG. 13 illustrates a retraction device of the present invention havinga woven web member as it is being held prior to insertion into asurgical incision of a body;

FIG. 14 illustrates a cross-section view of a ring member having an ovalshape;

FIG. 15 illustrates a cross-section view of a ring member having asquare shape;

FIG. 16 illustrates a cross-section view of a ring member having acircular shape;

FIG. 17 illustrates a cross-section view of a ring member having an ovalshape and an internal lumen;

FIG. 18 illustrates a cross-section view of a ring member having asquare shape and an internal lumen;

FIG. 19 illustrates a cross-section view of a ring member having acircular shape and an internal lumen;

FIG. 20 illustrates a cross-section view of a ring member having a pairof vertical ovals connected along the long axes;

FIG. 21 illustrates a cross-section view of a ring member having a pairof vertical ovals connected along the short axes;

FIG. 22 illustrates a cross-section view of a ring member having aconnected pair of circles;

FIG. 23 illustrates a cross-section view of a circular ring memberhaving a lumen and a reinforcement member placed therein;

FIG. 24 illustrates a cross-section view of a circular ring memberhaving a plurality of lumens and reinforcement members placed within thelumens; and

FIG. 25 illustrates a cross-section view of an oval ring member having alumen and a biasing reinforcement member placed within the lumen.

DESCRIPTION OF PREFERRED EMBODIMENTS AND BEST MODE OF THE INVENTION

Surgical procedures often require that tissues and organs be temporarilyrepositioned to provide a clear visual path for the surgeon. Forexample, FIGS. 1(a) and 1(b) illustrate the arterial and venous systems,respectively, of a human being that is often covered or obscured by bodytissues and/or organs that may need to be repositioned during a surgicalprocedure. The obscuring tissues and/or organs may be the abdominalcontent such as the intestines, bowel, fat, etc., as illustrated in FIG.2, which may need to be relocated and held in a preferred position awayfrom the point of surgery. FIG. 3 illustrates a retraction device 10 ofthe present invention that may be placed in a surgical area such as theabdominal area to provide an unobstructed workplace 7., The retractiondevice 10 operates to retract or reposition abdominal content 5 awayfrom the immediate workplace 7. Once the retraction device 10 isproperly placed in the abdominal area, the surgeon will have a clear andreasonably unobstructed view of the operative site.

Referring to FIGS. 4 and 5, the retraction device 10 of the presentinvention comprises a ring member or wire element 15 that is made of amalleable material. That is, the ring member 15 is bendable and willstay bent in the shape or form in which it is bent. The ring member 15may include first bending portions 22, 23 and second bending portions24, 25, 26 and 27. The first bending portions 22, 23 may be used to foldthe ring member 15 in half bringing opposing portions 28, 29 toward eachother as illustrated in FIG. 5. Once the ring member 15 is folded inhalf along the first bending portions 22, 23, the second bendingportions 24, 25, 26 and 27 may then be bent to form substantiallystraight portions 200, 210 as illustrated in FIG. 4. It is appreciatedthat the ring member 15 may have a plurality of bending portions and maybe bent in any shape depending on the needs of each particular surgicalprocedure.

Referring to FIGS. 6-8, the ring member 15 of the retraction device 10is illustrated in a flat, low profile condition that is suitable forinsertion into a surgical incision. The ring member 15 has a front ringsurface 30, a back ring surface 31, an inner ring surface 32, and anouter ring surface 33. The ring member 15 further includes substantiallyparallel portions 34, 35 that may be squeezed together forming the lowprofile condition. The ring member 15 may support a membrane or webstructure 60 such as a fabric cover that is fixedly attached to thefront ring surface 30 as illustrated in FIG. 8, the back ring surface 31as illustrated in FIG. 7, or to both the front and back ring surfaces 30and 31. It is foreseeable that the membrane 60 may be fixedly attachedto at least one of the inner ring surface 32 and the outer ring surface33.

The membrane or web structure 60 is preferably flexible such that it canretain tissues and organs of different shapes and sizes. Furthermore,the membrane or web structure 60 should be able to retain both hard andsoft tissues such as the muscles and bowel during abdominal surgery.Specifically, the retraction device 10 and membrane 60 should be tautenough to securely hold and separate hard tissues and organs and, at thesame time, be flexible enough to gently retain soft tissues and organsso as not to damage the tissues and organs or affect their circulation.The membrane 60 is preferably transparent so that tissues and organs areviewable through the membrane. An advantage of this feature is it allowsa surgeon to view and ascertain the condition of a tissue or organduring a surgical procedure.

Once the retraction device 10 is flattened, it may be inserted into asurgical incision 102 as generally illustrated in FIGS. 9-11. Theretraction device 10 may be inserted through the small incision 102because it is flattened and the retraction device 10 does not fullyexpand to its final shape until it is partially or fully inserted to apoint well within the abdominal cavity. As illustrated in FIGS. 12 and13, the retraction device 10 may be flattened by squeezing along sides40, 45 of the ring member 15 in a first condition to facilitateinsertion. It is appreciated that the membrane 60 is also sized andconfigured to stretch and recover in response to the shaping andreshaping of the ring member 15. The membrane 60 may be a bias-woven orknitted fabric that exhibits elastic properties. Alternatively, themembrane 60 may be constructed of any elastic material that responds tothe shaping and reshaping of the ring member 15.

The ring member may have different cross-sectional shapes andconfigurations as illustrated in FIGS. 14-22. Each of thecross-sectional shapes of the ring member provides a bending bias in apreferred plane. For instance, the ring member of FIG. 14 has an ovalshape 50 providing a preference for bending along the long axis overbending along the short axis., That is, a retraction device having anoval ring member will be easier to bend and shape along the long axisthan along the short axis. In addition, the region bent along the longaxis is more resilient than the region bent along the short axis. As aresult, the strongest retraction for this configuration is developed inthat portion which comprises a bend along the long axis. In anotherembodiment of the invention, FIG. 15 illustrates a cross-section view ofacting member having a substantially square shape 52 that bends equallyin two planes but resists bending diagonally. An additional embodimentmay also include a ring member having a rectangular cross-section thatprovides preferential bending in one plane and increased resistance tobending in the opposite plane. The rectangular cross-section would alsosubstantially resist bending diagonally.

FIG. 16 illustrates a ring member having a circular cross-section 54where the entire ring member may bend equally in all directions and thatyields only to the forces applied by the membrane 60. The circularcross-section 54 is therefore shapeable to a greater degree in alldirections than other geometries and may allow the retraction device tobe placed in awkward positions or to be shaped in a manner that avoidsdelicate or sensitive structures. It is appreciated that the ring membermay have a cross-section of any shape or geometry to provide a desiredbending bias in a preferred plane.

Referring to FIGS. 17-19, each of the ring members of FIGS. 14-16,respectively, may include an internal lumen 56 defining a wall 57. Thewall 57 may be circular or form a shape that provides a desired bendingbias. That is, the lumen 56 may impart a bending bias in a similarmanner as the various cross-sections of the ring members discussedabove. The relationship between the wall 57 of the lumen 56 and asurface 58 of the ring member may also impact the bending bias. Forexample, the thickness of the wall 57, i.e., the distance between thewall 57 and the surface 58 of the ring member, may determine a bendingbias. In another embodiment of the invention, a reinforcement member 315is placed within a lumen 305 to provide additional bending bias asillustrated in FIG. 23. The reinforcement member 315 may comprise aplastic component, a metal component or any combination thereof. Themetal component may include aluminum, titanium, stainless steel or anycombination of these compounds.

The reinforcement member 315 may be inserted and placed in a preferredlocation along the lumen 305 so that a preferred bending bias isdeveloped in specific regions along the lumen 305 of the ring member.For instance, referring back to FIGS. 4 and 5, a preferred embodimentmay require that a section or, sections 28, 29 of the retraction device10 be substantially straight whereas sections 24, 25, 26 and 27 arebendable. In this case, a rigid reinforcement member may be placed alongthe sections 28, 29 to keep these sections substantially straight. Asecond, more resilient reinforcement member, may then be placed adjacentto the first, more rigid reinforcement member within the lumen toprevent the first reinforcement member from shifting position along thelumen.

In yet another embodiment of the invention, the reinforcement member 315comprises a material having a “shape memory” that enables thereinforcement member to return to its desired shape. With this design,the reinforcement member may be used with a retraction device that canbe severely deformed during insertion while maintaining the ability toreturn to its original shape or condition. The shape memory materials,for example, include a blend of nickel and titanium metals, which arealso commonly referred to as Nitenol®. In particular, a retractiondevice would be constructed with a reinforcement member comprisingNitenol®, or the like, in a preferred shape and condition, theretraction device would then be subjected to cold temperature so that itbecomes malleable or flexible. During use, the retraction device wouldbe bent to facilitate insertion into a preferred location. Onceinserted, the reinforcement member would warm to body temperature andreturn to the preferred shape and condition, thereby returning theretraction device to its original shape and condition. An advantage ofthe reinforcement member of the invention is it allows the ring memberto be severely deformed, even beyond the normal elastic limits of thematerial from which the ring member is constructed.

Moreover, the reinforcement member has very good resistance to kinkingand permanent deformation because it is constructed of, e.g.,nickel-titanium alloys. That is, with this construction, thereinforcement member of the invention placed within the lumen of thering member can prevent the ring member from being overstressed orkinked. In addition, the reinforcement member may allow the retractiondevice to be compressed or folded or otherwise reshaped into a conditionthat allows it to be inserted into a body cavity through the smallestpossible surgical incision.

FIGS. 20-22 illustrate ring members 200, 210 and 220, respectively,comprising a plurality of cords in accordance with additionalembodiments of the invention. The cords of ring members 200, 210 and 220may be constructed according to previously discussed geometriccross-sectional shapes or profiles. FIG. 20 illustrates the ring member200 comprising a pair of oval cords 202, 204 that are vertically joinedat point 206 along the long axes of the cords 202, 204. FIG. 21illustrates the ring member 210 comprising a pair of oval cords 212, 214that are vertically joined at point 216 along the short axes of thecords 212, 214. In yet another embodiment of the invention, FIG. 22illustrates the ring member 220 comprising a pair of circular cords 222,224 joined at point 226 along the length of each of the cords 222, 224.Each of the ring members 200, 210 and 220 exhibits bending preferencesin accordance with the individual cord geometries combined with theoverall geometry of the connected cords.

In each of the above embodiments, the ring members were formed bycombining two cords; however, it is appreciated that a plurality of cordelements comprising three or more individual cords may be combined toexhibit a desired bending preference. It is further noted that each ofthe above constructions may be achieved by extrusion of material havinga cross-section that resembles a combination of cords or by the actualconnection of individual cord elements. In addition, the combined cordsmay be contained within the lumen of a covering tube or wrap.

As discussed above, FIG. 23 illustrates a cross-section view of a ringmember 300 having an internal lumen 305 and a reinforcement member 315placed within the lumen 305. The lumen 305 defines a wall 310. In thisembodiment, the reinforcement member 315 has a cross-sectional shape orprofile that is different from the cross-sectional shape or profile ofthe ring member 300. For example, the ring member 300 may have acircular cross-section while the reinforcement member 315 may have arectangular cross-section. With a different cross-sectional shape orprofile, the reinforcement member 315 may impart a different bendingbias on the ring member 300. It is appreciated that the ring member 300,reinforcement member 315 and wall 310 may have different cross-sectionalshapes or profiles from one another to provide a desired bending bias ina preferred plane.

FIG. 24 illustrates a ring member 325 having a plurality of internallumens 330, 335 that may or may not communicate with one another inaccordance with another embodiment of the invention. The ring member 325further includes reinforcement members 350, 355 that may be insertedinto the lumens 330, 335, respectively, to provide a desired bendingbias of a retraction device. In another embodiment of the invention,FIG. 25 illustrates a ring member 370 having an oval cross section, around or oval lumen 375, and a rectangular reinforcement member 380placed within the lumen 375. The configuration of ring member 370provides a bending bias that allows the retraction device to be shapedor bent in a preferred plane while providing great strength in anopposite plane.

Many alterations and modifications may be made by those having ordinaryskill in the art without departing from the spirit and scope of theinvention. Therefore, it must be understood that the illustratedembodiments have been set forth only for the purposes of examples andthat they should not be taken as limiting the invention.

1. A retraction device 10 adapted to temporarily reposition body tissuesand organs during a surgical procedure, comprising: a malleable ringmember 15 comprising a plurality of bending portions 24, 25, 26, 27adapted to be twisted, folded, bent or deformed to be inserted into asurgical incision; and a membrane 60 fixedly attached around theperimeter of the ring member
 15. 2. The retraction device of claim 1,wherein the membrane 60 is a flexible fabric operable to retain the bodytissues and organs of different shapes and sizes.
 3. The retractiondevice of claim 1, wherein the membrane 60 is capable to retaining bothhard and soft body tissues and organs during surgery.
 4. The retractiondevice of claim 1, wherein the bending portions 24, 25, 26, 27 and themembrane 60 are taut enough to securely hold and separate hard tissuesand organs yet are flexible enough to gently retain soft tissues andorgans so as to damage the tissues and organs or affect theircirculation.
 5. The retraction device of claim 1, wherein the membrane60 is transparent.
 6. The retraction device of claim 1, wherein themembrane 60 is sized and configured to stretch and recover to theshaping and reshaping of the ring member
 15. 7. The retraction device ofclaim 1, wherein the membrane 60 is a bias woven or knitted fabric. 8.The retraction device of claim 1, wherein the membrane 60 is formed ofany elastic material that responds to the shaping and reshaping of thering member
 15. 9. The retraction device of claim 1, wherein the ringmember 15 has an oval cross-section providing a preference for bendingalong the long axis.
 10. The retraction device of claim 1, wherein thering member 15 has a substantially square cross-section providing equalpreference to bending in both axes or planes and resistance to bendingdiagonally.
 11. The retraction device of claim 1, wherein the ringmember 15 has a circular cross-section.
 12. The retraction device ofclaim 1, wherein the ring member 15 further comprises an internal lumen56 defining a wall
 57. 13. The retraction device of claim 12, whereinthe wall 57 has a circular cross-section or a cross-section of anygeometric shape providing a desired bending bias.
 14. The retractiondevice of claim 12, wherein the ring member 15 further comprises areinforcement member 315 placed within the lumen 56 to provideadditional bending bias.
 15. The retraction device of claim 14, whereinthe reinforcement member 315 comprises at least a plastic component anda metallic component.
 16. The retraction device of claim 15, wherein themetallic component includes at least one of aluminum, titanium andstainless steel.
 17. The retraction device of claim 14, wherein thereinforcement member 315 is placed in some sections 28, 29 of the ringmember 15 to keep said sections 28, 29 substantially straight.
 18. Theretraction device of claim 14, wherein the reinforcement member 315comprises a shape memory material including Nitenol.
 19. The retractiondevice of claim 1, wherein the ring member 15 comprises a plurality ofcords 202, 204, said cords 202, 204 are vertically joined at a point 206along vertical axes of the cords 202,
 204. 20. The retraction device ofclaim 19, wherein the cords 202, 204 have oval cross-sections.
 21. Theretraction device of claim 14, wherein the reinforcement member 315 hasa first cross-section and the ring member 15 has a second cross-sectiondifferent in shape from the first cross-section.
 22. The retractiondevice of claim 21, wherein the first cross-section of the reinforcementmember 315 is rectangular and the second cross-section of the ringmember 15 is circular.
 23. The retraction device of claim 14, whereineach of the ring member 15, the reinforcement member 315 and the wall 57has a cross-section or a profile of any geometric shape to provide adesired bending bias in a preferred plane.
 24. The retraction device ofclaim 21, wherein the reinforcement member 315 imparts a differentbending bias on the ring member
 15. 25. The retraction device of claim14, wherein the ring member 325 further comprises a second lumen 335 anda second reinforcement member 355 placed within the second lumen 335.26. A method for operating a retraction device 10 adapted to repositionbody tissues and organs during a surgical procedure, comprising thesteps of: providing a malleable ring member 15 having a plurality ofbending portions 24, 25, 26, 27 and a membrane 60 fixedly attachedaround the perimeter of the ring member 15, said portions 24, 25, 26, 27adapted to be twisted, folded, bent or deformed to be inserted into asurgical incision; inserting the ring member 15 into the surgicalincision to provide an operable area; and twisting, folding, bending ordeforming the portions 24, 25, 26, 27 of the ring member 15 during thesurgical procedure to reposition the body tissues and organs.
 27. Themethod of claim 26, further comprising the step of removing the ringmember 15 from the operable area by twisting, folding, bending ordeforming the portions 24, 25, 26, 27 and puling them through thesurgical incision after surgery.
 28. The method of claim 26, wherein themembrane 60 is a flexible fabric operable to retain the body tissues andorgans of different shapes and sizes.
 29. The method of claim 26,wherein the membrane 60 is capable to retaining both hard and soft bodytissues and organs during surgery.
 30. The method of claim 26, whereinthe ring member 15 further comprises an internal lumen 56 defining awall
 57. 31. The method of claim 30, wherein the wall 57 has a circularcross-section or a cross-section of any geometric shape providing adesired bending bias.
 32. The method of claim 30, wherein the ringmember 15 further comprises a reinforcement member 315 placed within thelumen 56 to provide additional bending bias.
 33. The method of claim 32,wherein the reinforcement member 315 comprises at least a plasticcomponent and a metallic component.
 34. The method of claim 32, whereinthe reinforcement member 315 is placed in some sections 28, 29 of thering member 15 to keep said sections 28, 29 substantially straight.